text: /*
   *
   * some helper function for simple DVB cards which simply DMA the
   * complete transport stream and let the computer sort everything else
   * (i.e. we are using the software demux, ...).  Also uses the
   * video-buf to manage DMA buffers.
   *
   * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   */
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/device.h>
  #include <linux/fs.h>
  #include <linux/kthread.h>
  #include <linux/file.h>
  #include <linux/slab.h>
  
  #include <linux/freezer.h>
  
  #include <media/videobuf-core.h>
  #include <media/videobuf-dvb.h>
  
  /* ------------------------------------------------------------------ */
  
  MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
  MODULE_LICENSE("GPL");
  
  static unsigned int debug;
  module_param(debug, int, 0644);
  MODULE_PARM_DESC(debug,"enable debug messages");
  
  #define dprintk(fmt, arg...)	if (debug)			\
  	printk(KERN_DEBUG "%s/dvb: " fmt, dvb->name , ## arg)
  
  /* ------------------------------------------------------------------ */
  
  static int videobuf_dvb_thread(void *data)
  {
  	struct videobuf_dvb *dvb = data;
  	struct videobuf_buffer *buf;
  	unsigned long flags;
  	void *outp;
  
  	dprintk("dvb thread started\n");
  	set_freezable();
  	videobuf_read_start(&dvb->dvbq);
  
  	for (;;) {
  		/* fetch next buffer */
  		buf = list_entry(dvb->dvbq.stream.next,
  				 struct videobuf_buffer, stream);
  		list_del(&buf->stream);
  		videobuf_waiton(&dvb->dvbq, buf, 0, 1);
  
  		/* no more feeds left or stop_feed() asked us to quit */
  		if (0 == dvb->nfeeds)
  			break;
  		if (kthread_should_stop())
  			break;
  		try_to_freeze();
  
  		/* feed buffer data to demux */
  		outp = videobuf_queue_to_vaddr(&dvb->dvbq, buf);
  
  		if (buf->state == VIDEOBUF_DONE)
  			dvb_dmx_swfilter(&dvb->demux, outp,
  					 buf->size);
  
  		/* requeue buffer */
  		list_add_tail(&buf->stream,&dvb->dvbq.stream);
  		spin_lock_irqsave(dvb->dvbq.irqlock,flags);
  		dvb->dvbq.ops->buf_queue(&dvb->dvbq,buf);
  		spin_unlock_irqrestore(dvb->dvbq.irqlock,flags);
  	}
  
  	videobuf_read_stop(&dvb->dvbq);
  	dprintk("dvb thread stopped\n");
  
  	/* Hmm, linux becomes *very* unhappy without this ... */
  	while (!kthread_should_stop()) {
  		set_current_state(TASK_INTERRUPTIBLE);
  		schedule();
  	}
  	return 0;
  }
  
  static int videobuf_dvb_start_feed(struct dvb_demux_feed *feed)
  {
  	struct dvb_demux *demux  = feed->demux;
  	struct videobuf_dvb *dvb = demux->priv;
  	int rc;
  
  	if (!demux->dmx.frontend)
  		return -EINVAL;
  
  	mutex_lock(&dvb->lock);
  	dvb->nfeeds++;
  	rc = dvb->nfeeds;
  
  	if (NULL != dvb->thread)
  		goto out;
  	dvb->thread = kthread_run(videobuf_dvb_thread,
  				  dvb, "%s dvb", dvb->name);
  	if (IS_ERR(dvb->thread)) {
  		rc = PTR_ERR(dvb->thread);
  		dvb->thread = NULL;
  	}
  
  out:
  	mutex_unlock(&dvb->lock);
  	return rc;
  }
  
  static int videobuf_dvb_stop_feed(struct dvb_demux_feed *feed)
  {
  	struct dvb_demux *demux  = feed->demux;
  	struct videobuf_dvb *dvb = demux->priv;
  	int err = 0;
  
  	mutex_lock(&dvb->lock);
  	dvb->nfeeds--;
  	if (0 == dvb->nfeeds  &&  NULL != dvb->thread) {
  		err = kthread_stop(dvb->thread);
  		dvb->thread = NULL;
  	}
  	mutex_unlock(&dvb->lock);
  	return err;
  }
  
  static int videobuf_dvb_register_adapter(struct videobuf_dvb_frontends *fe,
  			  struct module *module,
  			  void *adapter_priv,
  			  struct device *device,
  			  char *adapter_name,
  			  short *adapter_nr,
  			  int mfe_shared)
  {
  	int result;
  
  	mutex_init(&fe->lock);
  
  	/* register adapter */
  	result = dvb_register_adapter(&fe->adapter, adapter_name, module,
  		device, adapter_nr);
  	if (result < 0) {
  		printk(KERN_WARNING "%s: dvb_register_adapter failed (errno = %d)\n",
  		       adapter_name, result);
  	}
  	fe->adapter.priv = adapter_priv;
  	fe->adapter.mfe_shared = mfe_shared;
  
  	return result;
  }
  
  static int videobuf_dvb_register_frontend(struct dvb_adapter *adapter,
  	struct videobuf_dvb *dvb)
  {
  	int result;
  
  	/* register frontend */
  	result = dvb_register_frontend(adapter, dvb->frontend);
  	if (result < 0) {
  		printk(KERN_WARNING "%s: dvb_register_frontend failed (errno = %d)\n",
  		       dvb->name, result);
  		goto fail_frontend;
  	}
  
  	/* register demux stuff */
  	dvb->demux.dmx.capabilities =
  		DMX_TS_FILTERING | DMX_SECTION_FILTERING |
  		DMX_MEMORY_BASED_FILTERING;
  	dvb->demux.priv       = dvb;
  	dvb->demux.filternum  = 256;
  	dvb->demux.feednum    = 256;
  	dvb->demux.start_feed = videobuf_dvb_start_feed;
  	dvb->demux.stop_feed  = videobuf_dvb_stop_feed;
  	result = dvb_dmx_init(&dvb->demux);
  	if (result < 0) {
  		printk(KERN_WARNING "%s: dvb_dmx_init failed (errno = %d)\n",
  		       dvb->name, result);
  		goto fail_dmx;
  	}
  
  	dvb->dmxdev.filternum    = 256;
  	dvb->dmxdev.demux        = &dvb->demux.dmx;
  	dvb->dmxdev.capabilities = 0;
  	result = dvb_dmxdev_init(&dvb->dmxdev, adapter);
  
  	if (result < 0) {
  		printk(KERN_WARNING "%s: dvb_dmxdev_init failed (errno = %d)\n",
  		       dvb->name, result);
  		goto fail_dmxdev;
  	}
  
  	dvb->fe_hw.source = DMX_FRONTEND_0;
  	result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_hw);
  	if (result < 0) {
  		printk(KERN_WARNING "%s: add_frontend failed (DMX_FRONTEND_0, errno = %d)\n",
  		       dvb->name, result);
  		goto fail_fe_hw;
  	}
  
  	dvb->fe_mem.source = DMX_MEMORY_FE;
  	result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_mem);
  	if (result < 0) {
  		printk(KERN_WARNING "%s: add_frontend failed (DMX_MEMORY_FE, errno = %d)\n",
  		       dvb->name, result);
  		goto fail_fe_mem;
  	}
  
  	result = dvb->demux.dmx.connect_frontend(&dvb->demux.dmx, &dvb->fe_hw);
  	if (result < 0) {
  		printk(KERN_WARNING "%s: connect_frontend failed (errno = %d)\n",
  		       dvb->name, result);
  		goto fail_fe_conn;
  	}
  
  	/* register network adapter */
  	result = dvb_net_init(adapter, &dvb->net, &dvb->demux.dmx);
  	if (result < 0) {
  		printk(KERN_WARNING "%s: dvb_net_init failed (errno = %d)\n",
  		       dvb->name, result);
  		goto fail_fe_conn;
  	}
  	return 0;
  
  fail_fe_conn:
  	dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_mem);
  fail_fe_mem:
  	dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_hw);
  fail_fe_hw:
  	dvb_dmxdev_release(&dvb->dmxdev);
  fail_dmxdev:
  	dvb_dmx_release(&dvb->demux);
  fail_dmx:
  	dvb_unregister_frontend(dvb->frontend);
  fail_frontend:
  	dvb_frontend_detach(dvb->frontend);
  	dvb->frontend = NULL;
  
  	return result;
  }
  
  /* ------------------------------------------------------------------ */
  /* Register a single adapter and one or more frontends */
  int videobuf_dvb_register_bus(struct videobuf_dvb_frontends *f,
  			  struct module *module,
  			  void *adapter_priv,
  			  struct device *device,
  			  short *adapter_nr,
  			  int mfe_shared)
  {
  	struct list_head *list, *q;
  	struct videobuf_dvb_frontend *fe;
  	int res;
  
  	fe = videobuf_dvb_get_frontend(f, 1);
  	if (!fe) {
  		printk(KERN_WARNING "Unable to register the adapter which has no frontends\n");
  		return -EINVAL;
  	}
  
  	/* Bring up the adapter */
  	res = videobuf_dvb_register_adapter(f, module, adapter_priv, device,
  		fe->dvb.name, adapter_nr, mfe_shared);
  	if (res < 0) {
  		printk(KERN_WARNING "videobuf_dvb_register_adapter failed (errno = %d)\n", res);
  		return res;
  	}
  
  	/* Attach all of the frontends to the adapter */
  	mutex_lock(&f->lock);
  	list_for_each_safe(list, q, &f->felist) {
  		fe = list_entry(list, struct videobuf_dvb_frontend, felist);
  		res = videobuf_dvb_register_frontend(&f->adapter, &fe->dvb);
  		if (res < 0) {
  			printk(KERN_WARNING "%s: videobuf_dvb_register_frontend failed (errno = %d)\n",
  				fe->dvb.name, res);
  			goto err;
  		}
  	}
  	mutex_unlock(&f->lock);
  	return 0;
  
  err:
  	mutex_unlock(&f->lock);
  	videobuf_dvb_unregister_bus(f);
  	return res;
  }
  EXPORT_SYMBOL(videobuf_dvb_register_bus);
  
  void videobuf_dvb_unregister_bus(struct videobuf_dvb_frontends *f)
  {
  	videobuf_dvb_dealloc_frontends(f);
  
  	dvb_unregister_adapter(&f->adapter);
  }
  EXPORT_SYMBOL(videobuf_dvb_unregister_bus);
  
  struct videobuf_dvb_frontend *videobuf_dvb_get_frontend(
  	struct videobuf_dvb_frontends *f, int id)
  {
  	struct list_head *list, *q;
  	struct videobuf_dvb_frontend *fe, *ret = NULL;
  
  	mutex_lock(&f->lock);
  
  	list_for_each_safe(list, q, &f->felist) {
  		fe = list_entry(list, struct videobuf_dvb_frontend, felist);
  		if (fe->id == id) {
  			ret = fe;
  			break;
  		}
  	}
  
  	mutex_unlock(&f->lock);
  
  	return ret;
  }
  EXPORT_SYMBOL(videobuf_dvb_get_frontend);
  
  int videobuf_dvb_find_frontend(struct videobuf_dvb_frontends *f,
  	struct dvb_frontend *p)
  {
  	struct list_head *list, *q;
  	struct videobuf_dvb_frontend *fe = NULL;
  	int ret = 0;
  
  	mutex_lock(&f->lock);
  
  	list_for_each_safe(list, q, &f->felist) {
  		fe = list_entry(list, struct videobuf_dvb_frontend, felist);
  		if (fe->dvb.frontend == p) {
  			ret = fe->id;
  			break;
  		}
  	}
  
  	mutex_unlock(&f->lock);
  
  	return ret;
  }
  EXPORT_SYMBOL(videobuf_dvb_find_frontend);
  
  struct videobuf_dvb_frontend *videobuf_dvb_alloc_frontend(
  	struct videobuf_dvb_frontends *f, int id)
  {
  	struct videobuf_dvb_frontend *fe;
  
  	fe = kzalloc(sizeof(struct videobuf_dvb_frontend), GFP_KERNEL);
  	if (fe == NULL)
  		goto fail_alloc;
  
  	fe->id = id;
  	mutex_init(&fe->dvb.lock);
  
  	mutex_lock(&f->lock);
  	list_add_tail(&fe->felist, &f->felist);
  	mutex_unlock(&f->lock);
  
  fail_alloc:
  	return fe;
  }
  EXPORT_SYMBOL(videobuf_dvb_alloc_frontend);
  
  void videobuf_dvb_dealloc_frontends(struct videobuf_dvb_frontends *f)
  {
  	struct list_head *list, *q;
  	struct videobuf_dvb_frontend *fe;
  
  	mutex_lock(&f->lock);
  	list_for_each_safe(list, q, &f->felist) {
  		fe = list_entry(list, struct videobuf_dvb_frontend, felist);
  		if (fe->dvb.net.dvbdev) {
  			dvb_net_release(&fe->dvb.net);
  			fe->dvb.demux.dmx.remove_frontend(&fe->dvb.demux.dmx,
  				&fe->dvb.fe_mem);
  			fe->dvb.demux.dmx.remove_frontend(&fe->dvb.demux.dmx,
  				&fe->dvb.fe_hw);
  			dvb_dmxdev_release(&fe->dvb.dmxdev);
  			dvb_dmx_release(&fe->dvb.demux);
  			dvb_unregister_frontend(fe->dvb.frontend);
  		}
  		if (fe->dvb.frontend)
  			/* always allocated, may have been reset */
  			dvb_frontend_detach(fe->dvb.frontend);
  		list_del(list); /* remove list entry */
  		kfree(fe);	/* free frontend allocation */
  	}
  	mutex_unlock(&f->lock);
  }
  EXPORT_SYMBOL(videobuf_dvb_dealloc_frontends);
  